1. Field of the Invention
The present invention is directed to a system for accessing stored messages over a wireless telephone network and, more particularly, to a system that utilizes a plurality of bearer channels to communicate commands and messages between a wireless telephone and the message storage system.
2. Description of the Related Art
Existing message storage and retrieval systems, sometimes also called xe2x80x9cenhanced services systemsxe2x80x9d, allow different types of messages, such as is voicemail, facsimile or e-mail messages, to be stored for later retrieval by subscribers of such systems. Examples of these systems are described in U.S. Pat. Nos. 5,029,199: 5,193,110; 5,260,990; 5,263,080; 5,475,748; 5,493,607; 5,524,139; 5,519,766 and 5,008,926, all incorporated herein by reference. Such systems allow a caller or sender to leave a message, such as a voicemail message, for a subscriber whenever the subscriber is not available. When a message is retrieved, the subscriber typically uses a telephone to call the system over a wireless or wire line telephone connection. The subscriber then presses keys on the telephone to generate touchtones to xe2x80x9clog onxe2x80x9d to the system, i.e. enter his or her mailbox number or passcode, and then to control the system, e.g. to command the system to play, save, delete, etc., the message. In these systems, the telephone connection between the subscriber""s telephone and the system must be established before the subscriber can obtain a listing of messages or select one or more of the messages for playback. In addition, this telephone connection must be maintained throughout the subscriber""s interactions with the system. This long-duration telephone connection poses problems, however, because a xe2x80x9cvoice portxe2x80x9d on the message storage system is occupied for the duration of the telephone connection, and these voice ports are expensive. Furthermore, if the subscriber uses a mobile, e.g. cellular, PCS, etc., telephone to access the system, the call occupies a wireless voice channel for the duration of the telephone connection, and these channels are also expensive.
It is, therefore, an object of the present invention to reduce the amount of time a voice channel is required when a subscriber accesses his or her mailbox.
It is also an object to reduce the amount of time a voice port is required when a subscriber accesses his or her mailbox.
It is an additional object to provide an authorized subscriber access to his or her messages without requiring the subscriber to enter his or her mailbox number or passcode.
It Is a further object to provide a simple visual interface to a message storage system that simplifies the tasks associated with message access and administration.
A typical wireless telephone handset includes a display screen. Many modem wireless telephone handsets also include a limited-function browser (a xe2x80x9cmicro-browserxe2x80x9d). The present invention utilizes this screen and micro-browser to display a list of messages, including voicemail messages, facsimile messages or e-mail messages, that are stored in a subscriber""s mailbox by a message storage system. Using this screen and micro-browser and keys on the handset, the subscriber can select and manipulate one or more of the messages, such as causing the message to be displayed on the screen (if it is a text or graphic message), played over the telephone (if it is a voice message or a message that can be converted to speech), deleted, saved or forwarded. The list of messages can include information, such as a caller""s name or telephone number, the time a message was deposited, the type of message, e.g. voice, facsimile or e-mail, and an indication of urgency of the message. This information can be displayed on the screen to facilitate the subscriber""s message selection. Using buttons on the handset, the subscriber can scroll through the list of messages and select one or more of these messages to be acted upon.
A wireless connection between a wireless telephone handset and a base station carries one or more so-called xe2x80x9cbearerxe2x80x9d channels, including a voice bearer and a data bearer, e.g. CDPD or GSM-CSD, although in many wireless telephone systems only one bearer channel can be active at a time. Typically, at least one of the data bearer channels is established whenever the handset is powered on, even if the handset is not actively handling a voice call. Some data carried over the data channels are used by the wireless telephone system to supervise the handset and maintain the wireless connection between the handset and the base station, such as to alert the handset of an incoming call, send the digits of an outgoing call or control the radio channels, i.e. frequencies, on which the handset transmits and receives. The data channels are, however, also available to carry data between the handset and systems outside the wireless telephone network.
The micro-browser communicates over one of these bearer channels, preferably a data channel, with the message storage system to receive data, such as a list of messages, from the message storage system and to command the system to perform functions, such as to send the list of messages or delete a particular message, selected by the subscriber. Preferably, when sending commands or exchanging data with the message storage system, the micro-browser communicates with a xe2x80x9cgatewayxe2x80x9d, which, in turn, communicates over a a data network, such as the Internet, to the message storage system.
According to the present invention, a voice bearer channel need not be established for the subscriber to obtain a list of messages in the mailbox or to select one of these messages, e.g. for deletion or playback. Similarly, no voice port Is used on the message storage system to provide this list of messages or process other commands, e.g. delete a message.
Commands sent by the micro-browser to the message storage system have associated information that identifies the subscriber, such as the subscriber""s account number on the gateway, the mobile identification number xe2x80x9cMINxe2x80x9d) or telephone number of the wireless handset, the subscriber""s mailbox number or other information that can be mapped to the subscriber""s mailbox number. This information enables the message storage system to access the correct mailbox. The message storage system maintains a data structure or queries a database that correlates the subscriber identification information with the subscriber""s mailbox number. This data structure or database includes the telephone number of the subscriber""s handset.
When it becomes necessary to send voice signals between the handset and the message storage system, such as to play or record a message or greeting, the handset establishes a voice channel, typically by placing a voice call to the message storage system, and communicates with the message storage system over the voice channel. Since the message storage system typically handles many subscribers concurrently, it is necessary for the message storage system to correlate voice calls it receives over the telephone network with commands it receives over data channels. Prior to establishing the voice channel, the handset commands the message storage system to expect a voice call from a particular wireless handset and, when this call is received, to perform a desired function, such as playing or recording voice signals carried over that voice call. The command received by the message storage system identifies the handset, from which a call is expected, e.g. by specifying the handset""s MIN or telephone number or otherwise identifying the subscriber who issued the command. If necessary, the message storage system consults its data structure or database to ascertain the telephone number of the subscriber""s handset and ultimately the subscriber""s mailbox number. Each wireless handset has a unique telephone number, and when a call arrives at the message storage system, the telephone network provides the message storage system with the calling handset""s telephone number (xe2x80x9ccalling line IDxe2x80x9d or xe2x80x9cCLIxe2x80x9d). The message storage system uses this CLI to associate (xe2x80x9cintegratexe2x80x9d) the incoming call with the command that was previously received over the data channel.
Advantageously, the subscriber is not required to enter his or her mailbox number or passcode before accessing his or her messages, as would be required if the subscriber called a conventional message storage system, because the commands sent by the micro-browser to the message storage system identify the subscriber, and only the subscriber, or a person authorized by the subscriber, has access to subscriber""s handset.
In wireless telephone systems in which only one bearer channel can be active at a time, the data channel must be tom down before the voice channel is established. Once the voice channel is established, the handset can exchange subsequent commands and data with the message storage system over the voice channel, e.g. by sending or receiving touchtone, modem, frequency-shift keying (FSK) or other signals to or from the message storage system. Alternatively, the handset can cause the voice channel to be torn down after the voice signals have been sent, and the handset can reestablish a data channel and once again exchange commands and data with the message storage system over the data channel.
In wireless telephone systems in which the voice channel can operate concurrently with a data channel, such as two-way SMS or USSD, the handset can exchange commands and data with the message storage system over the data channel, and it can exchange voice signals over the voice channel, without tearing down either channel.
In other embodiments, the voice signals are encoded and sent over the data channel. In these embodiments, no voice channel is required, and commands, data and encoded voice signals are carried over the data channel.